An increasingly common battlefield hazard encountered by military vehicles is the land mine. As a consequence, much work is being done to create blast resistant vehicle floors and to create seat assemblies that protect soldiers from shocks caused by mine blasts. Typically during a blast, the floor of the vehicle buckles upward rapidly. If the soldier's feet are then resting on the floor and if the soldier's lower legs are oriented vertically above the feet, then the floor's motion will cause a force transfer up the legs to the soldier's knees. A sufficient force will severely injure the knees. I have developed an improvement to seat assemblies that prevents such a force transfer and thereby protects the soldier's knees.